Abstract: A fluid machine includes an electric motor, a pump, an inverter, and a housing having a motor chamber and an inverter chamber. The housing has a cooling passage having an inverter cooling passage and a motor cooling passage through which cooling fluid flows. After the cooling fluid is introduced to the inverter cooling passage, a flow of the cooling fluid is divided at the inlet into a flow of the cooling fluid flowing through the inverter cooling passage and a flow of the cooling fluid flowing through the motor cooling passage, the flow of the cooling fluid flowing through the inverter cooling passage and the flow of the cooling fluid flowing through the motor cooling passage are joined together at the outlet and discharged from the inverter cooling passage. The inverter cooling passage has a passage expanded portion in which a vortex flow is generated.

Abstract: A fluid machine includes an electric motor, a pump, an inverter, and a housing having a motor chamber and an inverter chamber. The housing has a cooling passage having an inverter cooling passage and a motor cooling passage through which cooling fluid flows. After the cooling fluid is introduced to the inverter cooling passage, a flow of the cooling fluid is divided at the inlet into a flow of the cooling fluid flowing through the inverter cooling passage and a flow of the cooling fluid flowing through the motor cooling passage, the flow of the cooling fluid flowing through the inverter cooling passage and the flow of the cooling fluid flowing through the motor cooling passage are joined together at the outlet and discharged from the inverter cooling passage. The inverter cooling passage has a passage expanded portion in which a vortex flow is generated.

Abstract: A screw fluid machine includes a screw-shaped male rotor having formed helically therearound teeth and a screw-shaped female rotor having formed helically therearound grooves. The female rotor is engaged with the male rotor. A housing accommodates therein the male and female rotors. A working chamber is defined by the housing and the male and female rotors. Lead angles of the teeth and the grooves decrease from an inlet toward an outlet. An outline of each tooth includes a pair of first arc portions whose arc center is located on a pitch circle of the male rotor, and a second arc portion provided between the first arc portions. An outline of each groove includes a pair of third arc portions corresponding with the first arc portions, and a fourth arc portion substantially corresponding with the second arc portion.